In a manufacturing operation using an assembly line procedure the operation is supported by the regular supply of assembly parts to work stations alongside the assembly line. If the assembly parts are large articles or sub-assemblies, it is common to transport such parts in movable racks or cargo containers in which the parts are carried in an ordered array. The rack usually includes a retaining mechanism or rail structure for holding the parts in position and securing them from impact while in transit. The retaining mechanism also permits loading and unloading of the parts from the rack.
In a rack typical of the type used for a large scale manufacturing operation, e.g. automotive assembly, the retaining mechanism may be in the form of a bar or similar restraint. A problem encountered with known storage racks in such an environment is the need to disassemble, remove and reassemble the retaining mechanism with each supply cycle. This requirement yields certain practical disadvantages, i.e., it is an inefficient use of worker time and there is a tendency to misplace and mishandle the retaining mechanism causing loss, damage and inconvenience.